Foot/Footwear Sterilization System

ABSTRACT

A foot/shoe sanitizing system includes a housing having at least one opening and at least one ultraviolet emitting device supported within the housing. The ultraviolet emitting devices direct ultraviolet light around and/or through the set of foot/shoe support bars towards the foot or shoe placed on the foot/shoe support bars. The ultraviolet emitting devices are controllably powered to emit ultraviolet light and/or ozone onto the foot/shoe. In a preferred embodiment, the ultraviolet emitting device emits light that includes short wavelength ultraviolet light, causing the formation of ozone in the area of the shoe, thereby killing pathogens that are not easily killed with ultraviolet light alone. The system includes a sheet of activated carbon for catalyzing the ozone into harmless concentrations of carbon monoxide and carbon dioxide.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation in part of patent application Ser. No. 13/970,730, filed Aug. 20, 2013, which is a continuation in part of patent application Ser. No. 13/709,350, filed Dec. 10, 2012, now U.S. Pat. No. 8,617,479, which is a continuation in part of patent application Ser. No. 12/860,721, filed Aug. 20, 2010, now U.S. Pat. No. 8,624,202, which is a non-provisional application taking priority from U.S. provisional patent application Ser. No. 61/570,245, filed Dec. 13, 2011. The disclosures of both are hereby incorporated by reference.

FIELD

This invention relates to the field of disease control and more particularly to a system for reducing pathogens such as bacteria, viruses, fungi, spores, etc., on the feet and/or footwear.

BACKGROUND

Feet and footwear (shoes, sandals, socks, etc.) are carriers of multiple contamination agents that are often introduced into interiors of homes, hospitals, schools, and offices from various sources of contamination. Although any portion of the feet/footwear is known to carry/spread contamination, due to contact with contamination from surfaces (e.g. floor), the majority of contamination is carried on the bottom of footwear (or soles of feet).

Most contamination is inert, for example, dirt, sand, dust, leaves, etc. On the contrary, pathogens often lead to the spread of various diseases. A study by Dr. Charles Gerba, microbiologist and professor at the University of Arizona and The Rockport Company made in 2008 confirmed this finding. The study measured germs and microbes collected on footwear. What was found was a large number of bacteria both on the bottom and inside of shoes; averaging 420,000 units of bacteria on the outside of the shoe, and almost 3000 on the inside. The tested footwear picked up 420,000 units of bacteria in just two weeks. The bacteria included Escherichia coli, known to cause intestinal and urinary tract infections, meningitis and diarrheal disease; Klebsiella pneumonia, a common source for wound and bloodstream infections as well as pneumonia; and Serratia ficaria, a rare cause of infections in the respiratory tract and wounds.

Such germs/microbes/pathogens, in addition to other chemicals, are picked up by the feet/shoes in one place and deposited in another, leading to the spread of contamination, possibly to the shoes of other people, etc.

Cleaning/vacuuming of the floor may help reduce exposure to such germs/microbes, but has little or no effect on many. Furthermore, the germs/microbes are not neutralized by vacuuming and pose a health risk when emptying the vacuum cleaner. Using steam cleaners to kill the bacteria was found ineffective in killing germs and bacteria in homes and public places. At the source, the steam has a temperature of around 100 degrees C. but by the time the steam contacts the carpets or the floor, the temperature drops drastically and does not kill many bacteria and the viruses.

Applying chemical products by spraying or spreading on floors or carpets is also partially effective. To kill or disable most pathogens, a very strong chemical is required. As the strength of the chemical increases, so does the risk of potential hazards to health and safety of both the people applying the chemical and to the users of the cleaned surfaces. This is not to mention issues related to allergies. Stronger chemicals also tend to impact/discolor the surfaces on which they are applied. For example, bleach (chorine) is a known effective disinfectant, but bleach applied to one's shoes results in discolored shoes, and, therefore, would not be used by most. Furthermore, bleach (chlorine) does not kill many pathogens that have a protective shell

The feet/shoes cause a major concern, especially in hospital settings. Often, hospitals have isolation wards for people that have highly contagious diseases such as necrotizing fasciitis and Methicillin-resistant Staphylococcus aureus (MRSA). The hospitals attempt to control the spread of such diseases by maintaining a negative air pressure in these wards (so air flows in when a door is opened), constant filtration of the air in the wards, constant germicidal treatment, wearing of disposable outer garments, etc. For the lower extremities, at most, workers use booties to cover their footwear. The use of booties is a weak attempt to solve this problem, especially because the users of such booties use their hands to remove them from their feet.

The lack of diligence in reducing migration of microbes carried on feet/footwear is possibly responsible for an estimated 10% of new cases of disease such as MRSA each year, especially cases of such diseases that are contracted in hospitals. Many times, the hospitals are responsible for fighting these diseases without compensation due to the rationale that they were the source of the disease, resulting in billions of dollars in lost profits.

Beyond hospitals, many areas are also prone to breed germs/microbes and often travel on feet and shoes to homes, offices, etc. For example, public showers in gyms, schools, etc., often breed such microbes and, even after putting on shoes, these microbes get carried on the feet and shoes and often are deposited in homes and offices miles from the source.

Several techniques are known for reducing contamination from feet/shoes, especially for clean room environments in which it is important to limit particle contamination. For example, products used at the entrance to clean rooms include shoe vacuums with Hepa filters, sticky mats, and pressurized air flow to dislodge contaminates, all are only partially effective in removing/containing pathogens, while none actually kill germs.

What is needed is a system that will successfully reduce the number of microbes on one's feet and/or shoes and provide tracking and reporting features.

SUMMARY

In one embodiment, foot/shoe sanitizing system is disclosed including a housing having at least one opening and at least one ultraviolet emitting device is supported within the housing for emitting ultraviolet light on a shoe placed through the opening(s). The ultraviolet emitting devices are controllably powered by a source of power to emit ultraviolet light. In a preferred embodiment, the ultraviolet emitting device emits short wavelength ultraviolet light, causing the formation of ozone in the area of the shoe, thereby killing pathogens that are not easily killed with ultraviolet light alone. Further included is a device for detecting an identification of a user of the foot/shoe sanitizing system.

In another embodiment, a method of killing pathogens on a shoe is disclosed including providing the foot/shoe sanitizing device previously described and placing the shoe into one of the at least one openings. An identification of the user is obtained from the device for detecting an identification of a user. Next, emitting ultraviolet light from the at least one ultraviolet emitting device. The ultraviolet light passes through and/or around the foot/shoe support bars and radiates at least one of the pathogens on the shoe, thereby killing at least one of the pathogens. After sanitization, the shoe is removed from the at least one opening and a completion record is transmitted to a remote system through a network connection.

In another embodiment, a foot/shoe sanitizing system is disclosed including a housing having two openings, each of the openings size to allow entry of a shoe. The system has a processor and at least one ultraviolet emitting device supported within the housing. The at least one ultraviolet emitting device directs ultraviolet light onto a shoe placed within the openings under control of the processor. The system includes a source of power that powers each of the at least one ultraviolet emitting device controlled by the processor. One or more shoe sensors are operatively coupled to the processor to detect the presence of at least one shoe within one of the openings. An identification reading device is interface to the processor for determining the identification of a user of the system. In some embodiments, at least one of the ultraviolet emitting devices emits ultraviolet light that includes short wavelength ultraviolet light. The short wavelength ultraviolet light interacts with oxygen within the enclosure to produce ozone for improved termination of pathogens.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a perspective view of an exemplary system for reducing the number of pathogens on feet and/or shoes.

FIG. 1A illustrates a perspective view of an exemplary system for reducing the number of pathogens on feet and/or shoes with data logging.

FIG. 2 illustrates a front plan view of the exemplary system for reducing the number of pathogens on feet and/or shoes.

FIG. 3 illustrates a front plan cutaway view of the exemplary system for reducing the number of pathogens on feet and/or shoes.

FIG. 4 illustrates a perspective internal view of the exemplary system for reducing the number of pathogens on feet and/or shoes.

FIG. 5 illustrates a detail view of the active portion of the exemplary system for reducing the number of pathogens on feet and/or shoes.

FIG. 6 illustrates a perspective view of the reflector portion of the exemplary system for reducing the number of pathogens on feet and/or shoes.

FIG. 7 illustrates an exploded view of the exemplary system for reducing the number of pathogens on feet and/or shoes.

FIG. 8 illustrates block diagram showing an exemplary electrical system of the exemplary system for reducing the number of pathogens on feet and/or shoes.

DETAILED DESCRIPTION

Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures.

Throughout the remainder of this description, the term “pathogen” will be used generically to denote any germ, virus, prion, fungus, spore, microbe, or other pathogen, capable or not capable of infecting a mammal such as a human.

Additionally, the described system is shown in detail for deployment concerning one specific mammal, a human being, though it is anticipated that such system in possibly other embodiments be used for other mammals such as dogs, cats, horses, cows, etc. Furthermore, the described system is disclose in reference to feet and/or shoes for brevity and clarity purposes as it is fully understood that the described system will work for many objects including socks, slippers, etc. There are known risks of exposing certain parts of a mammal's body to certain wavelengths of ultraviolet light, therefore, it is anticipated that proper precautions are taken to reduce exposure and risk.

Referring to FIGS. 1 and 1A, perspective views of an exemplary system 10 for reducing the number of pathogens on feet and/or shoes are shown. It is anticipated that some elements of the system are present or absent is certain instantiations of the system. For example, in the system 10 for reducing the number of pathogens shown in FIG. 1, personal support arms 12 are present so that, as the user places feet/shoes into the brushes 32, the user has handles to hold onto to reduce the risk of falling and to ease stepping into the openings 32. In some embodiments, the handles are made from or coated with a microbe reducing material such as copper or silver nitrate, as known in the industry. In some embodiments, the handles are electrically isolated from the base portion 20 and/or include insulated coatings for electrical safety. In some embodiments, an area of the personal support arms, especially where a typical user will hold, is made from or is coated with a material that is known to reduce pathogens by contact with the skin of the user's hands. Such materials include, but are not limited to, copper, silver nitrate, etc.

In the examples shown in FIGS. 1 and 1A, the system 10 for reducing the number of pathogens has a base portion 20 has two openings 32 for insertion of each of the feet/shoes. It is well anticipated that, in other embodiments, any number of openings 32 are possible, such as one opening 32 or a whole bank of openings 32 for concurrent use for multiple people.

As will be shown in greater detail, the openings 32 are covered with bristles similar to two brushes that are intermeshed. The bristles 33 (see FIG. 2) will help prevent harmful radiation from exiting the base portion 20 which, otherwise, could harm the person using the system 10 for reducing the number of pathogens (e.g. certain radiations are known to cause vision problems). For completeness, the base portion 20 includes a lower cabinet 22 that provides structural support. Optionally, there is an opening 50 for cleaning the system 10 for reducing the number of pathogens.

In some embodiments, as shown in FIG. 1A, one or more identification sensors 7 a-d are included on the system 10. The identification sensor(s) 7 a-d detect an identity of a person who is operating the system 10 for reducing the number of pathogens. In some applications, it is important to encourage and/or require staff to make adequate use of the system 10 for reducing the number of pathogens. For example, in a fast food restaurant, policy may require that employees use the system 10 upon arrival to the facility, before entering a controlled area such as where food is prepared. Without a mechanism to detect who is using the system 10 and assuring sufficient exposure, some individuals may bypass the employer's requests/requirements and not utilize the system 10 properly.

Therefore, some embodiments of the system 10 include identification sensor(s) 7 a-7 d to record, log, and communicate usage of the system 10 so that the employer is able to determine who has made proper utilization of the system 10 and who needs behavior modification, etc.

Any identification detection mechanism 7 a-d is anticipated, either automatic or manual. An automatic detection mechanism does not require the user to present a badge or swipe a card, as is the case with RFID (Radio Frequency Identification Devices) sensors 7 c or short-range radio frequency emitter sensors 7 c (as used in the automotive industry to detect key fobs of authorized users of a vehicle), etc. Manual detection mechanisms require the user to perform an operation such as presenting a finger to a fingerprint scanner, entering a personal identification number (PIN) into a keypad 7 a, swiping a card or identification badge through a reader 7 b, presenting a bar code to a bar code scanner 7 d, etc.

With any form of identification sensor 7 a-d, the system 10 for reducing the number of pathogens correlates the operation of the system 10 and, optionally, the duration of use for reducing the number of pathogens with an individual associated with a specific identification. In some embodiments of the system 10 for reducing the number of pathogens uses this correlation to provide reports. For example, reports of when each employee used the system 10 for reducing the number of pathogens and/or the length of time each employee used the system 10 for reducing the number of pathogens, etc. In some embodiments of the system 10 for reducing the number of pathogens is linked to an employee time reporting system and uses this correlation to record shift start times, shift end times, break start times, break end times, room visit times (e.g. in hospitals), etc. In some embodiments of the system 10 for reducing the number of pathogens is linked to an employee database system and uses this correlation to record adherence to company policies. In some embodiments of the system 10 for reducing the number of pathogens is linked to an employee database and uses this correlation to enable operation, allowing only confirmed employees the ability to operate the system 10 for reducing the number of pathogens. As described in the description of FIG. 8, it is anticipated that the system 10 for reducing the number of pathogens is linked to a remote computer system 140 through a network 135 (wired or wireless) as known in the industry.

As an example, if each employee of the fast food restaurant is required to sterilize their shoes at the start of each shift, the system 10 for reducing the number of pathogens transmits usage events to an employee time reporting system. The employee is required to present their identification (badge, finger print, pin, etc.) and then sterilize their shoes using the system 10 for a specified length of time in order to be considered “on the clock.” In another example in a hospital, an employee (nurse, doctor, nutritional staff, cleaning staff, etc.) is required to sterilize their shoes upon entry and upon exit of a quarantined patient's room. Having employee correlation sensing, a system 10 for reducing the number of pathogens is located at the entry of each room and each employee is required to identify themselves to the system 10 and then to sterilize their shoes before entering and/or exiting the patient's room. Each sterilization cycle is recorded in a database for later reporting to assure proper usage.

In a preferred embodiment, one or more indicators 104 such as lamps or LEDs 104 are included. Although, as shown in FIG. 1A, the LEDs 104 are located in specific locations on the system 10, there is no limitation as to the number and/or location of the indicators 104. In some embodiments, the indicators illuminate with a color or pattern to indicate that the system 10 is idle and ready for use, for example, all indicators illuminate with a green color. In some embodiments, the indicators illuminate with a color or pattern to indicate that the system 10 is operating (in use and emitting ultraviolet radiation), for example, all indicators illuminate with a red color or all indicators blink at a certain rate. In some embodiments, the indicators illuminate with a color or pattern to indicate that the system 10 has malfunctioned (an internal error or a failed radiation emitter 70—see FIG. 3), for example, repeatedly, one or all indicators blink for a count and then are off for a period, where the count relates to one specific radiation emitter 70.

Referring to FIG. 2, a front plan view of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes is shown. The base portion 20 has a housing 22/30/34/36 that shields the user from harmful radiations. In this example, the housing sections 30/34/36 are spaced far enough apart as to allow a foot to be placed into the openings 32.

Radiation from the base portion 20 is reduced or sealed from radiating out of the base portion 20 (at least reduced to acceptable levels) by a deformable cover 33 which, in the embodiment shown, is a dense set of bristles 33. There are many ways to seal the openings after one inserts their feet/shoes into the openings 32, including the bristles 33 shown, other deformable materials, mechanical iris-type mechanism, etc., all of which are fully anticipated and included here within.

Again, for completeness, the base portion 20 includes a lower cabinet 22 that provides structural support. Optionally, there is an opening 50 for cleaning the reflectors 54/56 (see FIG. 6), which in this example is a pull-out drawer operated by a knob/handle 52.

Referring to FIG. 3, a front plan cutaway view of the lower cabinet 22 of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes is shown. In this, an exemplary placement of the radiation emitters 70, a set of foot/shoe support bars 80 and door 50 are shown, all of which will be described greater detail.

As will be discussed, one or more devices for sensing the presence of a user's foot are optionally provided to initiate emission of radiation when the user's foot is present or shortly thereafter. One such sensor is a light beam interruption sensor 90/92 (see FIG. 4). Another such sensor is a pressure sensor 25. A typical placement for a pressure sensor 25 is shown on the internal riser 82. By integrating the pressure sensor 25 into the internal riser 82, detection of mass from the left set of support bars 80, right set of support bars 80, or both is readily performed. The sensor 25 is used alone or in conjunction with the interrupt detection 90/92 (see FIG. 4) and/or other sensor devices.

Referring to FIG. 4, a perspective internal view of the base portion 22 of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes is shown.

For brevity, various mechanical subcomponents, supports, rubber feet, wires, etc., are not described as such are well known in the art.

Internal risers 80/82 support the mass of a user. In the example shown, the risers rest on a suitable support such as a base plate 21. Other internal components 80/82 are also mounted on the base plate 21. The exemplary system 10 for reducing the number of pathogens has one or more devices that emit radiation 70 (see FIG. 5 for better detail) that are powered/controlled by an electronic subsystem 96. Details of the electronic subsystem 96 are described along with FIG. 7. The electronic subsystem 96 receives power from an external source connected to the system by, for example, a power connector 98, or direct connection through a power cable, internal batteries, etc., as known in the industry.

Because of the potential harmful effects of radiation emanating from the devices that emit radiation 70, it is preferred (though not required) to have an interlock system that detects the presence of the user's foot/shoe on the grid 80. There are many known interlock systems that, for example, detecting the mass of a user (e.g. pressure sensor 25 shown in FIG. 3), detecting infrared radiation of the user, etc. It is anticipated that by detecting mass, the exemplary system 10 for reducing the number of pathogens has an additional feature of being selective on the mass of a user, not turning on, for example, for children and pets. It is anticipated that by using an infrared detector, the exemplary system 10 for reducing the number of pathogens is capable of operation only when an appendage of a mammal is present, thereby not operating when, for example, a child places a toy into one of the openings 32.

The example shown in FIG. 4 has a light beam interruption system having one or more emitter/receiver pairs 90/92 in which, placement of one or both feet/shoes in the openings 32 will interrupt a beam of light between block 90 and 92, thereby enabling the devices that emit radiation 70 to start emitting radiation. Note, it is anticipated that one block 90 have an emitter (e.g. light emitter) and the other block 92 have a receiver (e.g. light receiver) or vice versa, or in some embodiments, both the light emitter and light receiver are in one block 90 and the opposing block 92 is a reflector (passive). Because using a detector that is sensitive to light from ambient surroundings would, at times, prevent desired operation, it is also anticipated that the light emitted and detected be encoded or be of a specific wavelength that is not anticipated in the ambient surroundings. Furthermore, it is anticipated that there be one detector for each shoe such that, both shoes need to be inserted before the device(s) that emit radiation 70 are only activated when both (all) shoes are present. Further, it is also anticipated that a small amount of delay is inserted between detecting one or both shoes present and activating the device(s) that emit radiation 70.

In embodiments in which the user slides their shoes into the openings 32 of the system 10 for reducing the number of pathogens, at least one pair of emitter/receivers 90/92 is positioned forward within the openings 32 at a point at which the user's toes need to rest. In this way, operation of the system 10 for reducing the number of pathogen is only enabled when the user's foot is pushed completely forward. Again, any detection system is anticipated such as a forward mounted micro-switch that requires pressure from the toe of the user's shoe to enable operation.

Although not shown, it is also anticipated that there be an interlock device that detects when the door 50 is open to prevent leakage of radiation when the door 50 is ajar or open.

The support bars 80 protect the radiation emitting device(s) 70 from breakage due to the mass of the intended user while allowing sufficient radiation to reach the surfaces of the user's foot/shoe. The support bars 80 support the mass of the intended user. Although it is anticipated that a series of structural metal support bars 80 (or wires) are possible, portions of the user's foot/shoe located directly above such metal support bars 80 would receive less radiation, thus potentially not effectively neutralizing as many pathogens as possible. To increase the strength and distribution of the radiation from the radiation emitting device(s) 70, it is preferred that the support bars are made of glass, and in the preferred embodiments, be made of material that allows penetration of the desired wavelength of radiation from the radiation emitting device(s) 70. In some embodiments, the material is glass, but glass blocks certain UV wavelengths of radiation. In a preferred embodiment, the material is fused silica or fused quartz. These glass materials have superior transmission of both the ultraviolet and IR spectra radiations. For some applications, other materials such as ruby, synthetic ruby, and some polymers capable of ultraviolet transmission are also anticipated. Any material that has sufficient structure as to support the intended user(s) and provides for transmission of the desired radiation is anticipated.

Referring to FIG. 5, a detail view of the active portion of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes is shown. In this view, the electronics 96 and interrupters 90/92 are not shown for simplicity reasons.

In the example shown, a plurality of support rods 80 are supported by three supports 82. The plurality of support rods 80 are positioned over the radiation emitting devices 70. In operation, when the user places a foot/shoe atop the support rods 80 and the radiation emitting devices 70 energized (e.g. the detector initiates operation), radiation from the radiation emitting devices 70 passes around and through the support rods 80 and radiates the user's foot/shoe. In the preferred embodiment, the support rods 80 are made of a material that attenuate as little of the radiation from the radiation emitting devices 70 as possible.

The radiation emitting devices 70 emit one or more wavelengths of radiation for the destruction of pathogens. Ultraviolet light (400 nm to 100 nm) is categorized into three basic ranges: UVA from 400 nm to 320 nm, UVB from 230 nm to 280 nm, and UVC from 280 nm to 100 nm. For germicidal applications, typically UVB light in the range of 280 nm to 240 nm has been shown to be most effective, with 254 nm having the highest efficiency in destroying pathogens.

In some embodiments, the radiation emitting devices 70 are ultraviolet emitters or ultraviolet light bulbs, often known as UV bulbs or LEDs, emitting light with wavelengths of between, for example, 400-100 nm. Such ultraviolet light is known to kill at least a subset of known pathogens and, therefore, this light is suitable to reduce the number of pathogens on one's foot/shoe.

Although ultraviolet light kills some pathogens and is suitable for that purpose, ultraviolet radiation alone is not effective in killing certain pathogens or classes of pathogens, especially pathogens that have protective envelopes or shells that protect the pathogens from the environment until the pathogens find their way into a suitable environment for growth, such as a wound. An example of such a pathogen is C-diff, which has a hard outer shell and is not significantly affected by UVC radiation. Bleach has been found effective in breaking this outer shell and killing C-diff, but bleach is impractical for use on feet or shoes.

Lower wavelengths of ultraviolet light will ionize oxygen producing ozone (O₃). For many uses of ultraviolet light, ozone (O₃) production is an unwanted side effect of ultraviolet lamps. For such uses, the ultraviolet lamps are treated/coated to absorb ultraviolet light with wavelengths below 254 nm since these lower wavelengths of ultraviolet light will ionize oxygen. Again, this type of radiation emitting device 70 (ultraviolet bulb) is a possible alternative, being that this type of radiation emitting devices 70 will kill some class of pathogens.

Ozone has been found to be effective in killing some pathogens that cannot be effectively killed with ultraviolet light alone. Ozone is a strong oxidizing agent that breaks through the encapsulation of some of the more difficult pathogens to kill such as C-diff. Ozone is effective in bacterial disinfection and the inactivation of many viruses. Therefore, it is preferred to use a radiation emitting devices 70 that emit ultraviolet light in approximately the 240-250 nm range and also emit shorter wavelength ultraviolet light (e.g. approximately 180 nm) that will produce ozone in the presence of oxygen (O₂).

It is preferred to use radiation emitting devices 70 that includes emission of ultraviolet light in the UVC range and more particularly, in the approximately 180 nm wavelength range to ionize oxygen and purposely create ozone. Such specialized lamps that do not have the surface treatment that filters this wavelength are known and in use in other applications such as water sanitation, often known as germicidal lamps. Such lamps are suitable for use as the radiation emitting devices 70. These lamps are usually mercury vapor tubes similar to typical fluorescent light bulbs but without any phosphor coating and without any material that impedes the passing of ultraviolet light, including ultraviolet light in the 253.7 wavelength range which is very good at destroying pathogens. Therefore, these radiation emitting devices 70 emit a broader range of ultraviolet that includes the 254 nm wavelength and also shorter wavelengths (e.g. less than 240 nm) that break the bond between dioxygen molecules (O₂+UV->20), then the unstable oxygen atoms bond with another dioxygen molecule (O₂+O->O₃) forming ozone.

Certain wavelengths of ultraviolet light are harmful to humans and animals. Exposure to such is known to cause sunburn and eventually skin cancer. Exposure is also known to lead to temporary or permanent vision impairment by damaging the retina of the eye. For this reason, the radiation emitting devices 70 is shielded within the base portion 20 and are only illuminated when the presence of the user's foot/shoe is detected by, for example, sensors 90/92.

After sufficient exposure to the ultraviolet radiation and/or the ozone, it is desirable to dispose of the ozone. Because ozone is a powerful oxidant, ozone's high oxidizing potential, potentially, causes damage to mucus and respiratory tissues in animals, and also various tissues in plants. Such damage has been observed at concentration levels of about 100 parts per billion. Since ozone reacts with carbon to form carbon dioxide (CO₂), in some embodiments, part or the entire inside surfaces of the base portion 20 are coated with carbon or carbon granules 23 (see FIG. 7). Since ozone is heavier than air, the ozone will settle towards the bottom of the base portion 21 and combine with the carbon 23 to form carbon dioxide, which is a harmless gas in low concentrations. As an example, the base plate 21 has a coating of carbon granules 23 as shown in FIG. 7.

Although six independent radiation emitting devices 70 are shown (e.g. six germicidal lamps), any number of radiation emitting devices 70 are anticipated including one radiation emitting devices 70 and two radiation emitting devices 70 (one for each foot/shoe). The type of radiation emitting devices 70 is not limited in any way to any particular radiation emitting devices 70, though known germicidal lamps are shown as examples. It is also anticipated that some subset of the radiation emitting devices 70 emit ultraviolet at one wavelength or range of wavelengths and another subset of the radiation emitting devices 70 emit ultraviolet at a different wavelength or a different range of wavelengths.

Referring to FIG. 6, a perspective view of the concentrator portion of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes is shown. Since most radiation emitting devices 70 emit light in multiple directions, it is desirable to aim and direct as much of the emitted light towards the foot/shoe. For this, one or more reflectors 54/56 are situated beneath the radiation emitting devices 70. The reflector(s) 54/56 are preferably of a length compatible with the length of the radiation emitting devices 70 and are curved along an axis of the radiation emitting devices 70 to direct and scatter the ultraviolet light towards the foot/shoe.

It is well known for footwear to accumulate debris (in addition to the pathogens mentioned above). When/while the user is standing on the support bars 80, some of this debris will fall off and land on the reflector(s) 54/56. In some embodiments, to facilitate cleaning, the reflector(s) 54/56 are integrated into a removable assembly, as shown, having an access door cover 50 and, preferably, some mechanism that assists in pulling out the access door such as a knob or handle 52. In some embodiments, there is an interlock (not shown) that prevents emission of radiation from the radiation emitting devices 70 when the access door cover 50 is open. Alternately, in some embodiments, the lower cabinet 22 has openings that are formed in the shape of the reflector(s) 54/56 and the reflector(s) 54/56 are restricted so they cannot be removed from the openings, thereby, constantly blocking the openings and limiting the amount of radiation that is allowed to escape should the access door cover 50 be ajar during operation.

Referring to FIG. 7, an exploded view of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes is shown. In this view, it is possible to see one typical construction of the entire system 10 for reducing the number of pathogens, including the top surface onto which the housing sections 30/34/36 are mounted. Note that fasteners are not shown for brevity reasons. Fasteners are well known in the industry and are used where necessary.

Being that ozone (O₃) has more mass than oxygen (O₂) or Nitrogen (N₂) which are the primary gases in our atmosphere, ozone (O₃) produced by the radiation emitting devices 70 tend to gravitate to the bottom strata of the lower cabinet 22. Although small concentrations of ozone (O₃) is believe to be harmless to plants and animals, as a precautionary step, in some embodiments, a coating or sheet of carbon 23, preferably activated carbon, is located at the bottom of the lower cabinet 22. In a preferred alternate embodiment, the sheet of activated carbon 23 is a removable and replaceable fibrous activated carbon mat 23. This coating or sheet of activated carbon 23 functions similar to a catalytic converter, in which the activated carbon is oxidized by the ozone (O₃), depleting the ozone (O₃) and producing harmless levels of carbon dioxide (CO₂) and carbon monoxide (CO). The carbon mat 23 is exposed to ozone (O₃) during each operation of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes. Since the oxidation of the activated carbon in the carbon mat 23 or fibrous activated carbon mat 23 depletes layers of carbon, in a preferred embodiment, the carbon mat 23 or fibrous activated carbon mat 23 is replaceable with a new carbon mat 23 or fibrous activated carbon mat 23.

Referring to FIG. 8, block diagram showing an exemplary electrical system 96 of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes is shown. This is an example of one implementation, utilizing a processor 100 to control operation of the system 10 for reducing the number of pathogens. There are many other implementations anticipated, with or without the use of a processor 100 or processing element 100.

The exemplary processor-based sub-system 96 is shown having a single processor 100, though any number of processors 100 is anticipated. Many different computer architectures are known that accomplish similar results in a similar fashion and, again, the present invention is not limited in any way to any particular processor 100 or computer system. In this exemplary processor-based sub-system 96, the processor 100 executes or runs stored programs that are generally stored for execution within a memory 102. The processor 100 is any processor or a group of processors, for example an Intel 80C51 or processors that are known as Programmable Logic Controllers (PLCs). The memory 102 is connected to the processor as known in the industry and the memory 102 is any memory or combination of memory types suitable for operation with the processor 100, such as SRAM, DRAM, SDRAM, RDRAM, DDR, DDR-2, flash, EPROM, EEPROM, etc. The processor 100 is connected to various devices (e.g. sensors, relays, lights, etc.) by any known direct or bus connection.

For AC powered operation, AC power is conditioned and regulated by a power regulator 110, as known in the industry.

The power regulator 110 provides power for operation of the one or more devices that emit radiation 70, for the processor 100, and for any other component of the processor-based sub-system 96. In this example, one or more devices that emit radiation 70 are ultraviolet emitting bulbs 70, similar in operation to small florescent bulbs, though the present invention is not limited to any particular device that emits radiation 70. In general, such tubes 70 operate at a specific voltage and draw a typical amount of current per specifications from suppliers of such tubes 70. As the ultraviolet emitting bulbs 70 age or fail, such aging or failure is detected by monitoring of the current and/or voltage provided to the ultraviolet emitting bulbs 70 by one or more sensors 120/125. For example, one sensor 125 monitors voltage over the ultraviolet emitting bulbs 70 and another sensor 120 monitors current to/from the ultraviolet emitting bulbs 70. Outputs of the sensors 120/125 are connected to the processor 100. Upon detection of a failed or aging ultraviolet emitting bulb 70, the processor 100 signals such aging or failure by eliminating one or more lamps or LEDs 104, changing the color of one or more lamps or LEDs 104, emitting a sound through a transducer 106, and/or sending a message through the network 135 to, for example, an operations system (computer) 140 that is connected to the network 135. In such, the system 10 includes a network adapter or modem 130 to enable communication through the network 130 to, for example, an operations processor 140. This network adapter or modem 130 is any known communications interface, wired or wireless.

In some embodiments, the exemplary system 10 for reducing the number of pathogens on feet and/or shoes communicates with a remote system 140 for various reasons. In some embodiments, the exemplary system 10 for reducing the number of pathogens on feet and/or shoes communicates data regarding employee use of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes to the remote system 140 such as: “Employee 1234 operated system for 1.3 minutes.” In some embodiments, the exemplary system 10 for reducing the number of pathogens on feet and/or shoes communicates data regarding employee access to an area which includes the use of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes to the remote system 140 such as: “Employee 1234 operated system for 1.3 minutes then entered hospital room LL32.” In some embodiments, the exemplary system 10 for reducing the number of pathogens on feet and/or shoes communicates data regarding the identity of an employee and/or proper use of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes to the remote system 140 such as: “Employee 1234 verified and operated system for 1.3 minutes.” Responsive to such, if the identified employee is authorized to enter this room, the remote system 140 initiates unlocking and/or opening of an access to this room. In some embodiments, the exemplary system 10 for reducing the number of pathogens on feet and/or shoes communicates data regarding the identity of an employee and/or proper use of the exemplary system 10 for reducing the number of pathogens on feet and/or shoes to the remote system 140 such as: “Employee 1234 operated system for 1.3 minutes.” Responsive to such, the remote system 140 creates a time recording record (e.g. time clock function).

Being that it is difficult to discern which ultraviolet emitting bulbs 70 has aged or failed because the ultraviolet emitting bulbs 70 don't emit visible light and/or because it is harmful to expose one's eye to the light emitted by the ultraviolet emitting bulbs 70, in some embodiments, separate current sensors 120A are configured in series with each of the ultraviolet emitting bulbs 70, each current sensor 120A interfaced to the processor 100. In such, the processor 100 reads the current going to/from each of the ultraviolet emitting bulbs 70 and the processor 100 indicates which ultraviolet emitting bulb(s) 70 has aged or failed by eliminating the lamps/LEDs 104 in a certain pattern, colors, or sequence (e.g., blinking 3 times if the third ultraviolet emitting bulbs 70 has failed) and/or encoding an indication of the failed ultraviolet emitting bulb 70 in a message that is sent through the network 135 to an operations system 140.

Also in this example, one or more interruption sensor 90/92 (see FIG. 4) and/or pressure sensors 25 are interfaced to the processor 100. Any known and/or implemented shoe presence detector 90/92/25 is anticipated and is connected to the processor 100. The processor monitors the status of the shoe presence detector 90/92/25 and enables or disables operation of the ultraviolet emitting bulbs 70 through operation of a power switching device 115 (e.g. solid state switch 115 or relay 115). In such, it is also anticipated that the processor 100 illuminate one or more lamps or LEDs 104 to signal that the ultraviolet emitting bulbs 70 are operating after proper detection of the user's shoes and applying power to the ultraviolet emitting bulbs 70 through operation of the power switching device 115.

In some embodiments, instead of interrupter switches 90/92, one or more cameras 90/92, infrared sensors 90/92, ultrasonic detectors 90/92, or any known system for detecting and determining proper position of an object within the exemplary system 10 for reducing the number of pathogens on feet and/or shoes. In embodiments with such more advanced sensors 90/92, the size and position of each foot/shoe is determined to make sure a proper size foot/shoe is presented (e.g., not a foreign object) and to make sure the foot/shoe is positioned correctly for maximum exposure to UV light and/or ozone (O₃).

Once the processor 100 detects the presence of the user's shoes, the processor 100 closes the power switching device 115, thereby illuminating the ultraviolet emitting bulbs 70 for emission of the ultraviolet light onto the user's shoes. In some embodiments, the processor 100 also illuminates one or more lamps/LEDs 104 to provide feedback to the user that the sterilization process is in operation. In some embodiments, the processor 100 retains power to the ultraviolet emitting bulbs 70 until it is detected that the user has removed their shoes. In other embodiments, the processor 100 retains power to ultraviolet emitting bulbs 70 for a fixed length of time. In either embodiment, once the ultraviolet emitting bulbs 70 are shut off, any lamps/LEDs 104 that were illuminated are extinguished to indicate to the user that the sterilization has stopped.

In embodiments having identification detectors 7 a-7 d, the identification detectors 7 are interfaced to the processor as known in the industry, for example through a Universal Serial Bus interface (USB), a serial interface such as RS-232 or RS-422, RS-485, wireless connection, etc.

Once the identification is read by the processor 100 from the identification detector(s) 7, an optionally, the user's foot is detected by one or more sensors 90/92/25, the processor 100 initiates operation of the ultraviolet emitting devices 70 through, for example, the switch 115 to start the reduction of pathogens on the user's shoe. The processor indicates operation by, for example, illuminating one or more of the LEDs 104, in some embodiments with a specific color, sequence, pattern, etc. In some embodiments, the processor terminates the ultraviolet emission through, for example, the switch 115 after a period of time, which is either predetermined globally, predetermined based upon the identification of the user, determined by an entry on a device such as a keypad 7 a, or algorithmically determined based upon environmental factors such as the type of pathogens that are anticipated, the environment (e.g. pathogens are often more plentiful in warm, humid environments), etc. It is anticipated that the processor 100 query the remote operations system 140 to obtain information regarding the amount of exposure time, user identities, passwords/pins, current environmental conditions, pathogen alerts, etc. it is also anticipated that the system 10 include one or more environmental sensors (not shown), coupled to the processor 100 such as temperature sensors and humidity sensors, etc.

In some embodiments, once the processor terminates the ultraviolet emission, the processor notifies the user that the user of completion by, for example, illuminating or blanking one or more of the LEDs 104, in some embodiments with a specific color, sequence, pattern, etc. Also, in some embodiments, a completion record is created for the user. The completion record is transmitted to the operations processor 140 through the network 135, stored in the memory 102 for later retrieval, etc.

It is noted that the above example includes a processor-based system, but it is well known in the industry to replace the functionality of a processor with discrete components such as timers and sequential logic, etc.

Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result.

It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes. 

What is claimed is:
 1. A foot/shoe sanitizing system comprising: a housing having at least one opening; at least one ultraviolet emitting device supported within the housing, the at least one ultraviolet emitting device for directing ultraviolet light on a foot/shoe placed in the at least one opening; a source of power interfaced to each of the at least one ultraviolet emitting device, the source of power operatively powering each of the at least one ultraviolet emitting device, thereby the at least one ultraviolet emitting device emits ultraviolet light; means for detecting an identification of a user of the foot/shoe sanitizing system; and a carbon material located at the bottom of the housing.
 2. The foot/shoe sanitizing system of claim 1, wherein the carbon material is a sheet of activated carbon.
 3. The foot/shoe sanitizing system of claim 1, wherein the carbon material is a removable and replaceable sheet of activated carbon.
 4. The foot/shoe sanitizing system of claim 1, wherein the carbon material is a removable and replaceable fibrous activated carbon mat.
 5. The foot/shoe sanitizing system of claim 1, wherein the carbon material is a fibrous activated carbon mat.
 6. The foot/shoe sanitizing system of claim 1, wherein at least one of the at least one ultraviolet emitting device emits ultraviolet light with a wavelength below 240 nm, thereby causing O₂ molecules to split into two O₁ atoms and some of the O₁ atoms combining with other O₂ molecules to form ozone (O₃).
 7. The foot/shoe sanitizing system of claim 6, wherein the carbon material is oxidized by the ozone, thereby converting the ozone into carbon monoxide and/or carbon dioxide.
 8. The foot/shoe sanitizing system of claim 1, further comprising a wireless interface operatively interfaced to the means for detecting and wherein an identification record is sent through the wireless interface to a remote system.
 9. The foot/shoe sanitizing system of claim 8, wherein the remote system provides access based upon verification of the identification record that was sent sent by the means for detecting.
 10. A method of killing pathogens on a shoe, the method comprising: providing a foot/shoe sanitizing system comprising: a housing having at least one opening; at least one ultraviolet emitting device supported within the housing, the at least one ultraviolet emitting device directing ultraviolet light on a foot/shoe placed in the at least one opening; a source of power interfaced to each of the at least one ultraviolet emitting device, the source of power operatively powering each of the at least one ultraviolet emitting device, thereby the at least one ultraviolet emitting device emits ultraviolet light; means for detecting an identification of a user of the foot/shoe sanitizing system; and a activated carbon material located at the bottom of the housing; placing the shoe into one of the at least one opening; obtaining an identification of the user from the means for detecting; emitting ultraviolet light from the at least one ultraviolet emitting device, the ultraviolet light radiating at least one of the pathogens on the shoe, the ultraviolet light forming breaking oxygen molecules into singlet oxygen (O₁), some of the singlet oxygen combining with dioxygen (O₂) forming ozone (O₂); the ultraviolet light and the ozone killing at least one of the pathogens; removing the shoe from the at least one opening; and the ozone settling to the bottom of the housing and oxidizing the activated carbon material to form carbon monoxide (CO) and/or carbon dioxide (CO₂).
 11. The method of claim 10, wherein the activated carbon material is a sheet of activated carbon.
 12. The method of claim 10, wherein the activated carbon material is a removable and replaceable sheet of activated carbon.
 13. The method of claim 10, wherein the activated carbon material is a removable and replaceable fibrous activated carbon mat.
 14. The method of claim 10, wherein the activated carbon material is a fibrous activated carbon mat.
 15. A foot/shoe sanitizing device comprising: a housing having two openings, each of the openings sized to allow entry of a shoe; a processor, the processor located within the housing; at least one ultraviolet emitting device supported within the housing, the at least one ultraviolet emitting device for directing ultraviolet light onto shoes placed within the openings; a source of power, power to each of the at least one ultraviolet emitting device controlled by the processor, one or more shoe sensors, the shoe sensor(s) for detecting the presence of at least one of the shoes within one of the openings, the shoe sensor(s) are operatively coupled to the processor; and an activated carbon material within the housing.
 16. The foot/shoe sanitizing system of claim 15, wherein at least some of the ultraviolet light is at a wavelength below 240 nm which breaks oxygen molecules into singlet oxygen (O₁), and some of the singlet oxygen combining with dioxygen (O₂) forming ozone (O₃), the ozone for destroying pathogens on the foot/shoe, the activated carbon material for oxidizing the ozone to form carbon monoxide (CO) and/or carbon dioxide (CO₂).
 17. The foot/shoe sanitizing system of claim 15, wherein the activated carbon material is a sheet of activated carbon.
 18. The foot/shoe sanitizing system of claim 15, wherein the activated carbon material is a removable and replaceable sheet of activated carbon.
 19. The foot/shoe sanitizing system of claim 15, wherein the activated carbon material is a fibrous activated carbon mat.
 20. The foot/shoe sanitizing system of claim 18, wherein the fibrous activated carbon mat is removable and replaceable. 